Territory



(No Model.)

A. B. MELHOUSE.

DISTANCE INSTRUMENT.

No. 407,786. Patented July 30, 1889.

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UNITE STATES,

- Artnr Fries.

DISTANCE-INSTRUMENT.

SPECIFICATION forming part of Letters Patent No. 407,786, dated July 30,1889.

Application tiled March 8, 1889. Serial No. 302,508. (No model.)

To @ZZ whom, it may concern.-v

Be it known thatI, ANDREW B. MELHOUSE, a citizen'of the United States,residing at Villard, in the county of McHenry and Territory of Dakota,have invented certain new and useful Improvements inSurveying-Instruments; and I do declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to theletters and figures of reference marked thereon, which form a part ofthis specification.

This invention relates to certain new and useful improvements insurveyinginstruments, and has for its object to provide an instrument ofthis kind by which land may be surveyed without the use of. a chain, andby which the height of an object may be quickly and easily ascertained.

The novelty in the present instance resides in the peculiar combinationand the construction, arrangement, and adaptation of parts, all as morefully hereinafter described, shown in the drawings, and thenparticularly pointed out in the appended claim.

The invention is clearly illustrated in the accompanying drawings,which, with the letters of reference marked thereon, form a part of thisspecification, and in which- Figure lis a perspective view of myimproved instrument. Fig. 2 is a central vertical 'section through thesame, with the tele'- scopes, level, and compass removed.

Referring now to the details of the drawings by letter, A designates asuitable-base or support, provided with the circular scale B, marked offinto degrees and minutes, and

^ with an inner circular guide-line O. This scale and the guide-line maybe formed on the base; but I prefer to form them upon the narrowcircular metal piece a, which is secured to the base by screws, nails,or any other suitable fastenings. I prefer this construction for thereason that it decreases the bearing-surface of the carriage-room to bedescribed. This carriage D is formed of a bottom d and two sides d d2.To the under side ot' the bottom is screwed the cross-bar c, the ends ofwhich are formed on the arc of a circle, and in use are designed totravel within and be guided by the inner wall b of the scale B.

The bottom d of the carriage extends a short distance beyond the sides d(Z2, andhas its ends formed on the are of a circle and correspond withand ride upon the guide-line O.'

This bottom, instead of having its sides straight has them formed asshown best in Fig. l-that is, extending from a point near the center tothe periphery, so that in use points where the said sides touch theperiphery form convenient marks to designate the points where thecarriage stops when turned, as will be hereinafter more apparent. Thiscarriage is pivoted at the center of its bottom to the base A by meansof the vertical pin or pivot e, which extends through the said bot-tomand through the cross-bar c into a hole in the base in such a mannerthatthe carriage is tree to turn loosely and easily upon said pivot, for apurpose which will be soon apparent.

Fixed to one of the sides of the carriage is the disk D, which isgraduated or marked oit into degrees and minutes, and is arranged atright angles to the scale on the base, as shown.

E is a transverse pin or rod which finds bearings at its ends in thesides of the carriage, passing also through the center of the disk D, asshown.

F is a platform or plate having the downwardly-extending ears or lugsfat each end, which ears or lugs are provided with suitable holes oropenings through which the rod E is looselypassed, so as to allow saidplatform or plate to be tilted on said rod as a fulcrum when so desired.On this platform or plate F are iixed the two flanged plates or supportsg and g', one near the center, as shown, and the other to one sidethereof. These are designed to support each a. telescope, as indicatedby dotted lines at G and H in Fig. l.

Between the two flanged plates and between the two telescopes in use isplaced a level Lheld in place in any suitable manner, or irmly fixedthereon, as preferred. On the platform F, between the center telescopeand the vertical disk D, is a compass J, of any approved construction.The carriage is mov- IOO able on its pivot about its center on the base,and the platform is movable on the carriage in a plane at right anglesto that of the movement of the carriage. In use, by placing the centertelescope on a certain object and then marking the place on the scale Bon the base A, and then turning the carriage on its pivot so as to getthe other telescope on the same object and marking on the scale B theplace where the same registers, it will of course' point out on thescale a different point, giving a cross-line or two different pointswhich indicate the two sides of a triangle, and then by the use ofcertain rules known to surveyors the distance between the desiredobjects can be readily ascertained.

In order to ascertain the height of any desired object, it is onlynecessary to sight an object at the foot of the hill or other elevation;then place the instrument at a distance from the mentioned object andiind the dis- -tance between the instrument and said object in themanner above described; then fix the instrument level by means of thelevel 0n the platform, and mark the place on the disk D; then raise thetelescope or sight it at the top of the hill or elevation and mark theplace on the said disk, and you have a crossline, from which, by `ruleswell known to the art, the height of the elevation maybe read ilyascertained.

The device is simple, cheap, and in use will be found Very efiicient.

The combination., with the base and the carriage pivoted thereon on aVerticalpivot,

of the platform F, having downwardly-ex- JOHN L. SKJERDAL, ALBERT M.YOUNG.

